Method for web guiding of carpet material

ABSTRACT

A method for guiding a moving web material such as carpet or the like which has continuous longitudinal strands woven in parallel disposition, and which utilizes an invisible dye marker which is not readily apparent to normal viewing of the material after guiding and performance through certain processing stages. The method consists in applying selected luminescent dye marking materials to a selected thread or yarns during production of the web material and then utilizing line guide illumination and sensing responsive to selected luminescence to derive positioning signals which are then utilized through suitable control means to continually maintain lateral web position of the moving web material for trimming, rolling, etc. operations.

United States Patent Brown et al.

[451 Sept. 5, 1972 [54] METHOD FOR WEB GUIDING OF CARPET MATERIAL [72]Inventors: Jerald L. Brown, Oklahoma City, Okla; William O. Harlan,Atlanta,

2,968,856 1/1961 Allen ..26/51.5 3,041,703 7/1962 Prell ..26/5 1 .5

FOREIGN PATENTS OR APPLICATIONS 1,011,720 12/1965 Great Britain..250/2l9 WE [73] Assignee: Fife Corporation, Oklahoma City, PrimaryExaminer lames Kee Chi Okla. AttorneyDunlap, Laney, Hessin and Dougherty[22] Filed: Feb. 2, 1970 [57] ABSTRACT [211 App! 7504 A method forguiding a moving web material such as carpet or the like which hascontinuous longitudinal [52] US. Cl. ..139/l, 139/407, 26/515, strandswoven in parallel disposition, and which util- 250/219 3 izes aninvisible dye marker which is not readily ap- 51 Int. Cl. ..D03d 1/00,D03d 27/00, D03i 1/08 Parent to normal viewing of the material afterguiding [58] Field of Search ..139/ 1, 420, 407.1 B, 391; andPerformance thfollgh ceftam processmg stages' 2 515; 250 219 R, 219 WE,219 S The method consists in applying selected luminescent dye markingmaterials to a selected thread or yarns [56] References Cited duringproduction of the web material and then utilizing line guideillumination and sensing responsive to UNITED STATES PATENTS selectedluminescence to derive positioning signals which are then utilizedthrough suitable control means g M i to continually maintain lateral webposition of the 2638656 511953 zf zg 'g 26/51 5 moving web material fortrimming, rolling, etc. operan I I I u I n a l l I t' I 2,797,712 7/1957Shapiro ..139/407 x ms 2,838,762 6/1958 Wadely ..139/391 X 4 Claims, 5Drawing Figures L INL= COA/TPOL 5'EA/502 01w;-

WE-IS POS/T/OM/A/G A MECHANISM METHOD FOR WEB GUIDING OF CARPET MATERIALBACKGROUND OF THE INVENTION 1 Field of the Invention The inventionrelates generally to web guiding practices and, more particularly, butnot by way of limitation, it relates to an improved method for webmarking and guiding of continuous material woven with plurallongitudinal thread or yarn.

2. Description of the Prior Art The prior art includes many and variedtypes of web gliding apparatus for carrying out the guidance functionutilizing either the line guide or edge guide approach, and suchequipment may perform guidance in diverse cloth, paper and/or plasticprocessing situations. Prior art attempts at guidance of such as carpetmaterial has been difficult since generally relied upon sensingtechniques are seriously hampered by the uneven border and texture ofthe material itself. That is, due to the method of manufacture of carpetand the like, wherein the carpet backing may have irregular edgesvariably disposed outward from the tufting or weaving, conventionalguidance practices encounter various shortcomings due to materialsreflectivity, edge irregularity, thickness and bulk of material, andother intrinsic properties inherent with carpet and the like at theparticular stage of manufacture.

SUMMARY OF THE INVENTION The present invention contemplates a method forweb guiding wherein a normally invisible substance included in carpettufting is made to luminesce for detection by suitable line guide andweb positioning mechanism. In a more limited aspect, the inventionconsists of placing such invisible dye marker capable of fluorescence orphosphorescence on a selected yarn, thread or position along the web ofcarpet through integral weaving of the marking material; thereafter, themarker is stimulated and made to emit light whereupon the web can bemoved and properly positioned with line guide apparatus sensitive to theemitted light radiation of the dye marker to provide a lateral alignmentindication which is then applied to control suitable web positioningmechanism, thereby to maintain continual lateral positioning of themoving web through whatever the processing, printing, trimming or othersuch stages being performed.

Therefore, it is an object of the present invention to provide a novelmethod for tracking and guidance of a moving web of material woven withplural longitudinal yarns.

It is also an object of the invention to provide such a device for webguidance of carpet which enables edgetrimming of finished material withreduced wastage.

Finally, it is an object of the present invention to provide a webtracking method which enables line guiding of carpet having diversepatterns, textures, designs, etc; without reliance on edge uniformity.

Other objects and advantages of the invention will be evident from thefollowing detailed description when read in conjunction with theaccompanying drawings which illustrate the invention.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a functional block diagramillustrating the method of the invention;

FIG. 2 is a flow diagram showing steps performed in carrying out thenovel process;

FIG. 3 is a vertical sectional side view of one form of line guidesensing head which is suitable for carrying out the method of theinvention;

FIG. 4 is a vertical section taken transversely through the middle ofthe line guide sensing head as shown in FIG. 3; and

FIG. 5 illustrates a light mask which may be employed in the sensinghead of FIGS. 3 and 4.

DETAILED DESCRIPTION OF THE INVENTION The method of the presentinvention deals with structure and practice for maintaining movinglengths of longitudinally woven or tufted web material in linearalignment. Thus, as shown in FIG. 1, the material 10, made up of yarnsor tufting 12 and backing material 14 is maintained in longitudinalalignment through continual positioning by a suitable form of webpositioning mechanism 16. The web positioning mechanism 16 receivescontrol input from a control unit 18 which is energized in accordancewith input from a line sensor 20 responsive to a registry line 22. Theregistry line or marker yarn 22, shown as a triangular character, isactually formed as an invisible line which can be made to fluoresce oremanate such characteristic radiation for sensing by line sensor 20, aswill be further described in detail.

The registry line 22 may be effected by any of various solutions orsubstances applied to the web material at a desired lateral position sothat it is invisible under normal viewing but can be made to fluoresceor phosphoresce for sensing about the position. The invisible radiatingstripe of treated yarn or such can be formed using various solutions,e.g. zinc sulphide, selected organic and inorganic salts, and othermaterials to be described. Also, a phosphorescent pigment known asShannon Glow Pigment No. B-320 is commercially available from ShannonLuminous Materials Company of Los Angeles, Calif. This pigment iscapable of residual glow for several hours after exposure to light andmay find various specialized marking uses.

There are many materials, organic and inorganic, which are capable ofluminescing under selected stimuli to produce radiation suitable forline sensing purposes. Such luminescence may occur by eitherfluorescence, or phosphorescence. That is, initial persistence ofluminescent emission following the removal of excitation will dependupon the lifetime of the excited state. This initial emission decaysexponentially and is known as fluorescence. In many instances, there isalso an additional component of afterglow which decays more slowly. Thiscomponent is known as phosphorescence and it too may be utilized in linesensing applications.

The desirable luminescing properties are present in many organic andinorganic materials which may exist in suitable form for application aslinear markers. Generally, good organic materials may be the aromaticmolecules related to dyes such as the sodium salt of fluorescein indilute aqueous solution, Terphenyl in Xylene, Anthracene in Napthalene,Rhodamine and many other solutions and organic crystal gels andsuspensions. There are also numerous inorganic substances or phosphorshaving the desirable applications and marking properties, eg: certaindoped alkali halides, ZnS, and various silicates and phosphates properlysuspended in fluid form or as might be utilized in dust form.

The radiative material is applied to a selected portion or position ofthe moving web to provide the desired registry line for guide sensing.Thus, as shown in the flow diagram of FIG. 2, a selected dye markingsubstance 24 may be applied to dye a specific yarn in yarn supply 26prior to material production 28 and previous to any additional webprocessing 30. Thus, following arrow 32, the dye marking substance 24 iscontained in a selected skein of input yarn, i.e. the yarn forming aselected row of pile or tufting along backing 14, e.g. theantepenultimate warp yarn on a selected side. If desired, the dyemarking substance 24 can be washed or otherwise cleaned out of thefinished material after all processing is completed; however, it may notbe required since with some marker substances the fluorescent qualitydoes not usually persist for more than a few hours.

The inclusion of such as a marker yarn in initial weaving has also beenrecognized to be valuable in production of tire cord. In thisapplication the marker yarn is generally woven along a lateral mid-pointof the tire cord web. In any event, the dye marking substance shouldserve its function to enable web guiding through various stages ofmaterial coloring, printing, trimming through final roll-up, and in somecases the luminescing or fluorescing property will dissipate to leave novisible trace of the registry marker on the finished product.

One form of the line guide sensing head which is suitable for use in thepresent invisible line method is illustrated in FIGS. 3 and 4. A sensinghead 40 is disposed in close viewing relationship to material assupported to pass over a platen 42. The platen 42 is deemeddesirable tomaintain the plane of material 10 constant as changes in plane can causevariations in output of the sensing head 40.

Sensing head 40 consists of a housing 44 which is formed in generallyrectangular shape to contain a pair of fluorescence stimulation lightsources 46 and 48 as disposed on opposite sides of the interior ofhousing 44, and an optical unit 50 is affixed centrally therebetween.The fluorescing light sources 46 and 48 are suitably supported inelectrical contacting sockets 52 as disposed at opposite ends of housing44. A 1 10 volt line power input (not specifically shown) is applied inconventional manner to energize each of the light sources 46 and 48.

The fluorescing elements or light sources 46 and 48 may be any ofvarious types which are capable of irradiating the invisible line tocause emanation of the fluorescent radiation. One form of bulb whichgives good results is the General Electric type No. F4T5-BLB, a mercuryarc type of lamp which is coated to block white or visible light whilepassing largely black light for irradiation purposes.

The optical unit 50 is centrally secured by means of fasteners 54 withinthe housing 44 at a central location between light sources 46 and 48.The optical unit 50 contains a cylindrical lens 56 as secured across thebottom in viewing relationship to a marker yarn registry line 22 alongthe edge of material 10. A mask 58 may be disposed immediately abovelens 56 to define apertures 60 and 62 admitting fluorescing lightradiation to respective photo cells 64 and 66. The photo cells 64 and 66may be conventional photo cells, e.g. photoconductors of selectedsensitivity, and the electrical output is provided through respectiveleads 68 and 70 passing through feed-through grommet 72 for externalconnection to a suitable control unit such as control unit 18 (FIG. 1

The aperture mask 58 is formed with two apertures 60 and 62 which aretriangular in shape and arranged in oppositely-disposed orientation.Thus, when aperture mask 58 is aligned along the marker yarn registryline 22, any sideways movement of the line relative to aperture mask 58will cause oppositely varying light characteristics as viewed througheach of apertures 60 and 62. This form of edge or line guide detectionutilizing such as aperture mask 58 is fully taught in US. Pat. No.3,431,425 entitled System for Photoelectric Control of Moving Webs,"issued on Mar. 4, 1969 in the name of Brown et al. and assigned to thepresent assignee. The particular control unit and web positioningmechanism as disclosed in the above-identified patent may also findparticular use in carrying out the method of the present invention.

In performing the method with a device such as that of sensing head 40,it is important that the housing 44 be positioned down reasonably closeto the upper surface of the yarn or tufting 12. It has been found inpractice that placement of the cylindrical lens 56 no more thanone-quarter inch above yarn 12 will provide good tracking operation withdelivery of fluorescence generating illumination to cause emanation offluorescent light passing upward through cylindrical lens 56 to each ofthe photo cells 64 and 66.

Thus, in the case of web guiding of material 10, the marker yarn iswoven into the web at one or more places, depending upon requirements.The marked web is then moved continuously along its processing routewith the edge or such other portion having the marker yarn registry line22 passing beneath the optical unit 50. The energized light sources 46and 48 then irradiate the immediate portion of material 10 such that themarker yarn registry line 22 luminesces in detectable manner; That is,emanation of short-wavelength light, such as ultra violet, exciteselectrons to an upperenergy state to cause fluorescence which is thendetectable by the photo cells 64 and 66. These photo cells arepreferably chosen from photo-conductive or photo voltaic elements whichexhibit specific sensitivity at the luminescing light energywavelengths.

The fluorescent light emanating from marker yarn registry line 22 isthus collected through cylindrical lens 56 and directed to greaterconcentration upon each of photo cells 64 and 66. These photo cells 64and 66 are able to generate a differential signal output relative tolateral variations of registry line 22 due to the aperture mask 58. Thatis, the triangular mask openings 60 and 62 are oppositely disposed tocause inversely varying signal generation characteristics in response toside-wise movement of registry line 22. Such signal outputs from photocells 64 and 66 are then applied in conventional manner to control unit18 so that the sufficient necessary control signal output is applied toweb position mechanism 16 to re-position the material 10, i.e. to bringthe registry line 22 back to its center or nulling position.

It should be understood that while specific reference is made tofluorescent illumination and properties of suitable fluorescing dyemarker, there are many other materials and detectors which might gainadvantage of the luminescing property, i.e. either fluorescing orphosphorescing of the material, to emit characteristic radiation. Thus,black light irradiation of register line 22 with emission of fluorescentlight for detection in sensor photo cells 64 and 66 is but oneapplication which is suitable for the line sensing function. It may wellbe that the dye marking substance applied to form marker yarn registerline 22 is a substance capable of scintillating in the presence of suchas gamma or beta ray radiation whereupon phosphorescent illumination isemanating for sensing detection purposes.

No matter what the type of dye marker and detector used, the methodenables an essentially invisible marker yarn register line 22 to beplaced or integrally woven along a specific area or line on a web ofcarpet material, tire cord or such in non-destructive manner.Thereafter, the carpet or such web material can be processed throughvarious printing and trimming stages utilizing the marker yarn registryline 22.

One of the very valuable attributes with regard to carpet material isthe use of the invisibly dyed marker yarn as a register line 22 in thefinal processing stages, i.e. the carpet trimming operation. It isinherent in carpet manufacture that the backing 14 have relatively roughedge dimensions while the pile or weave tuft material 12 may bemaintained in its true, linear alignment. The backing material 14 is soirregular that carpet is generally trimmed by cutting a given, largedimension from the average edge registry in order that an even edge willbe finally produced. The necessity for trimming at an average distancealong the edge of the carpet backing results in great wastage of thecarpet material, and although various sensing devices have been tried,this wasteful edge trimming practice is prevalent in the carpetmanufacturing field.

Institution of the present method has enabled carpet to be trimmed byguiding the trimming mechanism relative to the invisible marker yarnregistry line 22. It would be possible to place invisible marker on theextreme outside pile or weave of the fabric; however, in the interest ofallowing some safety margin, and to give a better trim, it is thegeneral practice to weave the invisible dye marker yarn as the second orthird row of pile or tufting, and subsequently to scan the marker yarnin accordance with the present method to provide relative positionguidance to the trimming mechanism.

The foregoing discloses a novel method for web guidin g of wovenmaterials having particular characteristics which hamper or lessen theaccommodation of established techniques and systems. The present methodis particularly attractive due to the fact that the alignment mark canbe woven integrally with the web material with no outward visibleappearance, and even the fluorescing or phosphorescing property can beremoved or may soon loose its luminescent strength so that, in effect,the method can be employed with no aft r affects of vi ibl ature. hemethod is e o med Wit?! variations of exisiing equipment such t at it isessentially a low cost operation, especially when considering thepossibilities as to reduced wastage in processing and final trimming ofcertain carpet materials.

Changes may be made in the combination and arrangement of steps andelements as heretofore set forth in the specification and shown in thedrawings; it being understood that changes may be made in theembodiments disclosed without departing from the spirit and scope of theinvention. What is claimed is: 1. A method for web-guiding of a movingweb of carpet material for trimming and rolling operations, said web ofcarpet material having continuous warp components and utilizinginvisible dye marking substance having particular luminescencecharacteristics, comprising the steps of:

weaving a selected warp yarn as one of said warp components along saidweb of carpet material as a register point at a pre-selected transverseposition of the web proximate the outer edge warp component saidselected warp yarn carrying said invisible dye marking substance;irradiating said moving web proximate said transverse position to causepredetermined luminescence of said dye marking substance;

detecting transverse positional variations in said luminescenceindicative of transverse positional variations of said moving web;

generating a control function proportional to said de tected transversepositional variations in said luminescence;

re-positioning said moving web in an amount proportional to said controlfunction to counteract said transverse positional variations until saidinvisible dye marking substance is at said pre-selected transverseposition; and

processing including edge trimming of said moving web of carpet materialin order to form a carpet edge while maintaining minimal wastage of edgefabric of said carpet material and thus eliminating the need forovercutting with a selected safety margin.

2. A method as set forth in claim 1 which is further characterized inthat:

said invisible dye marking substance is fluorescent,

and said irradiation is black light to generate detectable lightemanations.

3. A method as set forth in claim 2 which is further characterized inthat:

said fluorescent substance is in liquid form and is contained throughouta selected yarn of said moving web continuously therealong.

4. A method as set forth in claim 1 which is further characterized inthat:

said invisible dye marking substance is a liquid substance capable ofemitting phosphorescent light radiation in response to characteristicirradiation.

1. A method for web-guiding of a moving web of carpet material fortrimming and rolling operations, said web of carpet material havingcontinuous warp components and utilizing invisible dye marking substancehaving particular luminescence characteristics, comprising the steps of:weaving a selected warp yarn as one of said warp components along saidweb of carpet material as a register point at a preselected transverseposition of the web proximate the outer edge warp component saidselected warp yarn carrying said invisible dye marking substance;irradiating said moving web proximate said transverse position to causepredetermined luminescence of said dye marking substance; detectingtransverse positional variations in said luminescence indicative oftransverse positional variations of said moving web; generating acontrol function proportional to said detected transverse positionalvariations in said luminescence; re-positioning said moving web in anamount proportional to said control function to counteract saidtransverse positional variations until said invisible dye markingsubstance is at said pre-selected transverse position; and processingincluding edge trimming of said moving web of carpet material in orderto form a carpet edge while maintaining minimal wastage of edge fabricof said carpet material and thus eliminating the need for overcuttingwith a selected safety margin.
 2. A method as set forth in claim 1 Whichis further characterized in that: said invisible dye marking substanceis fluorescent, and said irradiation is black light to generatedetectable light emanations.
 3. A method as set forth in claim 2 whichis further characterized in that: said fluorescent substance is inliquid form and is contained throughout a selected yarn of said movingweb continuously therealong.
 4. A method as set forth in claim 1 whichis further characterized in that: said invisible dye marking substanceis a liquid substance capable of emitting phosphorescent light radiationin response to characteristic irradiation.